Growler, pain, prednisone, ideas?

[Meligar]

Yesterday I came home to urine and feces outside of the litterbox. Trying to track down the culprit and noticed Growler trying to hide. Picked her up, she hissed, and when I felt her belly it was swollen.   Took her in to the vet this morning and he is not sure what is going on. She is in a lot of pain, touching her back might earn a bite and definitely a hiss. The doctor took an x-ray and there's no obvious problem, like tumor, or break or slipped disc or anything; her bladder was very full and she was full of feces, so the doctor expressed her bladder. He is thinking it could be a number of things--she is holding in her bowel movements because she hurt her back and it hurts to go, or her back could hurt because she has been holding in her bowels due to a bacterial infection or something similar. Could be a kidney problem.   Right now, we are going conservatively. I have her on strict crate rest isolated from her peers (but hanging out with the rest of the house, she seems to like being near the dogs and me). I am going to watch her elimination. Once she's chilled out a little, I am supposed to give her one half of a prednisone pill (the doctor wants to be very conservative with it because of the immunosuppressive quality of it, which made me happy) and clavamox. He gave her a shot of pain med and a shot of antibiotic. He did not give her a shot of prednisone because he wants to be very conservative in its use. If she does ok overnight, he wants me to continue with the antibiotic and hope that it clears up without further use of the prednisone. If she is still acting funky tomorrow, I have to call him for further instructions.   Is there anything else I should ask him to do? Anything I should look for? Anything else that would help? Her temp was a little elevated, but not a lot (if you feel her, externally she feels very hot though, the doctor was a little stumped by that, he kept expecting her temp to be higher). I want to ask for a full blood panel of all the cats, but I can't really think of a real reason except that I feel like, on a gut level, it would be a good idea to check kidney values, etc., all around. What kind of maintenance do you all do, what tests do you run regularly, where should my concern be?   Also, I would like to rave about my vet who paid half of my bill because he thinks it's nice i am trying to help these guys. So for medication, an exam, and an x-ray, I paid $75 today. It was a huge relief, and a very pleasant surprise. It's been a very stressful month; after losing Zest two weeks ago, my son has been in the hospital since Monday (he came home last night) with rotavirus after having a seizure. It was really worrisome to have to take Growler in today, but it was really nice that my vet has been so supportive, in his own gruff, low-tech way.   Melissa and the kittens in NJ